Credit for
the invention of photography is attributed variously to Joseph
Nicéphore Niépce (17651833), Louis
Daguerre (17871851), and William
Henry Fox Talbot (18001877). Talbot's discovery
of a process using a negative allowed the image to be printed
repeatedly, unreversed, on another medium such as paper. It is
this process that became the standard for photography until the
recent advent of digital photography. Most early use of photography
in books required that separately printed photographs be inserted
into each volume of an edition by hand, a costly process. By the
1880s, a much cheaper method had come into use: the halftone
photomechanical process used a screen to transform the photographic
image into dots. Depending on how the dots were reproduced, halftones
could be printed by relief or planographic printing methods. When
combined with the use of the three primary colors, halftones drove
out chromolithography for most color printing by the beginning
of the twentieth century.
Scientific
uses for photography were seen from the beginning. In
anatomy and in botany, the old graphic methods are still used
to illustrate general principles, since photography can show only
a specific human body or plant specimen.